Unfaithful /(?)/

Un·faith·ful

Unfaithful

a.
  1. Not faithful; not observant of promises, vows, allegiance, or duty; violating trust or confidence; treacherous; perfidious; as, an unfaithful subject; an unfaithful agent or servant.
    My feet, through wine, unfaithful to their weight.
    His honor rooted in dishonor stood, And faith unfaithful kept him falsely true.
  2. Not possessing faith; infidel. [R.]